We report photoluminescence from Si1-x-yGexCy films grown epitaxially on Si (100) by chemical vapor deposition. We observe significant energy shifts but no dramatic changes in the photoluminescence line shape caused by the presence of carbon. Using standard deformation potential theory to correct the epitaxial strain shifts, we conclude that the band gap of relaxed Si1-x-yGexCy alloys has a lower energy than the band gap of relaxed Si1-xGex with the same Si/Ge ratio. We propose an explanation of these results based on the assumption that carbon forms a resonant level within the conduction band of Si1-xGex.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)